Pusher device having adjustable tension



May 6, 1958 F. SMREKAR PUsHEE nEvIcE HAVING ADJUSTABLE TENSION 'Filed March I. 1957 INVENTOR. LARRY F SMREKAR pusher device should have a tine degree. oftei v 4*order to obtain: just the precise amount of required-@grip e onthe .stocks- Thisfgxipjmust A f 1and 4push thel stock vwhen necessaryta'nd also `belofable to slide alongrthestockdn the 4rearward.'moi/eineritythe -pusher when thel stock is.

invention provides ottension and the required amount of v,grip onjthel stock.

PUSHER- DEVICE `HAVING ADJUS'rABLE TENSION Larry F.'Smrekar, Solon,l Ohio,y assignor t0 The'Balas Collet Manufacturing Company, a corporation ofAOyhio Application March 1, 1957, Serial No 643,301 9 Claims. 5(Cl. 279-47) of the pads of a pusher to meet operating requirements.

"Another object is the Yprovision for obtaining `the amountof grip of a pusher upon stock being advanced l -by'the pusher to aline degree not otherwise obtainable.

-' -Another'object is the' provision forfobtaining in a novel and highly useful manner the precise amountl of -tension upon stock by a pusheruadvancing the'stock.

f AnotherI object is the provision for.obtaining;;unique f1 results by a new and usefulconstruction.

Other 'objects and a fuller'funderstandingof,my,inven Y"tionffmay, behad byrreferring to thevfollowingzdescription-'and claims, taken inconjunction uwith; the L accom- -Hpanying drawing,

in which: Figure 1 is a longitudinal sectional yvievwof aiorm of my device showing the device gripping aLpieceofrround Y stock;

-'sFigure y2 is a side elevational view of; the internal tubularrnernber of ymy f device;

'- YFigure 13 .is a lside elevational view ofthe external tubu larv member or shell of my devicefremovedA from the internal tubular member;

vFigure 4 is anendwise view lookingin. thegdirection Figure 5 is a cross-sectional view throughgthewline -5 of Figure 3.

y: ln fFignrefLI-showmy'device in assembledcondition .ftgripping al piece of -cylindricalstock llA whichfextends Y along the axis of my, {ff-used" for advancing collet 12 shown in broken lines. t. I:movement ofA n'iy'pusher` device,the stock' 11" ispmoying --.,\into1thecollet -12` while it is in an open device.' My pusher. device may# be the-Stock 111 in Aincrements to a 'f Upon each. reciprocal or relaxed posi- .ytionfandaftenthecollet 12 seizes or grips the,'.stock ,,then i -the= ,-pusher device slidestback along the stockA 11-` to a withdrawn position yWhere itvagain ,gripsl the stock ready l l for an advancing movement.v` Y

alternately'hold the stock 11V it-and then be able to slide along the stock to la ,with- HV.drawn vposition when the stock v y Becausethe vr'ushtlzr; must firmly'y enough tot: advance fis held b y-the .Cllet-the i on in besuch jas to. 'iiinilyT hold li mly held :by-thefcollet'.; My

.means for p obtainingLthis@ ne Vdegree i My device incorporates 1n.,,generalytwotubular inemimei-"tubular "member" lgwpreferably made of' suitable Figure 2. However,

"fingersl lare two opposed slots 14 which separate two opposed fingers which extend 18 and 19 disposed to engage and vsuiiciently to urge the pads ICC heat-treated steel, is split to have forwardly extending In `the form of the invention illustrated, there forwardly from a rear annular portion. The lingers of the inner member 13 are heattreated so as to be resilient and at the same time have the required degree of strength.

'Adjacent the forward end of the inner member 13 and facing the bore thereof are a pair of arcuate pads grip'the stock v'l1 extendingthroughV the pusher device; rlh'e resilient ngers of the inner member Vl?, are biased toward each other '18" and' l19 towardv each other when there is no stock between the pads so Vthat Vthe pads 1S and' 19 are heldin the position shown in this bias isy readily vovercome so that the lingers may be spread apart and the pads `18 and 19 separated by the insertion of the stock 1'1 into the pusher, 'such as shown in Figure l lt is to be noted However, this inwardly directed bias ofthe nger'sof the fthe setting and heat-treating of thc-.fingers vobtained only -by As yisk known, such a bias is not exact andit isl-clificultx tofpredetermember 13 alone,V as in Figure 2, is

- minedlyfx and maintain4 the exact degree..A requiredto operation of the pusher device. Z50-"proved device there ls t 'lingers to obtain the precise amount fof' grip-onf they stoclc` during Therefore;5 in -my' imonly` "suflicientfinwardf'lbias on: the hold the pads in the `positiorrshown inFigure 2;: but l do not depend uponthis bias setin the'ngers during manufacture of the,innerniember--Ifor obtainingtherequired degree of grip upon thestock'llzis aithreaded'portion At the rearwardmost endof the inner memberglil, there 15 which is threadablyengaged to atsupportio. This Vsupportlfl' carries the pushendevice andreeiprocatesY itY along i the pusher device.

its axis during the operation of A Atransverse notch-17 isfprovided in notch 17l being provided `for accommodatingfa cross pieceewhen it is desired to turn the-innen'memberf-l.

f ,Ins,hort, the notch 17 provides asurfaceforwrenching oftheinner member-'13. f n 1 j ,-positeslots 14.

There isa secondV `rear;annular portion of -threaded portion 21 hasn a somewhat largerk di y-than fli'erthreadd portion 15 l ,yanee of the threadedportionVIS.' T The threading -of the l .A Theforward end of theginnerl-member-13lihas acharn- -fered surface 20 extendingtherearoundq' chamfered surface 20 provides a tcammingfsurface inthe operation of tfmyoevice. Y i Y is at an angle ltothe axisv of .the

56:45 degrees and` preferably is at, anV anglein the rarge of lThe angular rdisposition V` ott. rthis surface device oftjmorejhan isless ,than 415 'd'eg'rees to the l rangev oflaboiit`A SOvdegrees to Thiscamming surface `20 is of the itubular member 13being interrupted; theop-v threaded portion l21 disposed on the the inner memberlrl fl'h ,and is" .pdsitioned 1n'. ad

Ithreadedportion 21 is similar vto'theV threading of the l shown,

i thr'eadedgportion 15.` Forexam'ple, vin ltliefillustration the threaded portion 1Swhas a leftfhandthread @and the' threaded portion 2r has Aa.1an-tantithread;

' ablyengage /thethreadedl portion 2110i 'the inneriember device vincludes a seco g2 "which isf concentrically mounted around. the.' inner member 13a. yTheouter tubular-meinber- 24.2 hasj'a rearad threaded* end portion 23a-which is adaptedtothread- @PatentedMay 6, 1958 walljof the inner :member 13; fthis` extends 'around thekioryvard wall I d tubular member or 'shell' four slots constitutes l. gspondingch padsl and n portions of slots `27,` 28, `29 and 30.r This `longitudinal `tension im- Y posed 3by the outer member 22 on the `camming surface p is adjustably determined byjturning the outer member 22 in sucha way` as'to change the longitudinalfposition por'tiony23 along the threaded portion 21. As `the outer ,"spirallydisposedslots 27, 28, 29.` and` 30 tend to extend .more parallel outer `member 22 and is in alignment with the camming ,1;

surface 20 of the inner tubular member the angular disposition of the shoulder 24 relative to the axis of the device is such as to complement the angular disposition of the camming surface 20, as for example, shown `in Figure l. member` 22 has a transverse notch 26 formed therein, this notch 26 being adapted to accommodate a crosspiece for the wrenching or turning of the outer member 22. l

Formed in the wall of the outer tubular member 22 intermediate of the planeof the shoulder 24 and tof the threaded portion 23 are four `slots 27, 28, 29- and 30. These slots are ingenerally spiral form and extend through `the wall of the outer tubular member 22. The

slots 27, 28, 29 and V30 are preferably equidistant from each other around thecircumferential extent of the tubular member 22. This :outer tubular member 22 is made of suitable steel and is heat-treated so that the tubular member 22 intermediate the lfour slots is resiliently distortable. In effect, the heat-treated steel between the four steel spirally disposed springs which may be resiliently elongated upon applying longitudinal tension to the tubular member 22.

` Uponfthe mounting of the outer tubular member 22 to the inner tubular memberf13 so as to concentrcally dispose them inthe relationship `shown in :Figure 1, the shoulder `24 is in longitudinal alignment with the.cam

ming surface' 20. i -By forcibly turning the outer tubular member `22 relative to the inner tubular member 13, such as by` using cross-piecesin the respective notches 17 ,and

26, .theA threaded interengagement of the threaded portions 21 and 23 of they respective members may be varied. By forcibly turning the tubular members relative to each other so `as to move the threaded portion 23 rearwardly, that is, alongitudinal `tension is applied to theouter tubular `member 22 by rea'soiifof the `abutment of the shoulder i 24 ontlie `cammiiJg-Psurface 20.` The resiliency of the slotted `tubular member 22.the`n is such `as to resiliently urge'the shoulder'2`4 rearwardly against the'camming surface 20. This longitudinal urging of the opposed surfaces .20 and 24 `camminglyforces `the opposed fingers `of the radially inward` and thus'increases the grip of the pads 1a .mais upon the stock 11; A nue degree of adjustmentof this grip on the stock maybe obtained by` turning the members '13 and 22 relative to each other so as to vary the threadedinterengagement `ofthe complementarythreaded portions 21,` and 23. A

' relatively small amount of turning of the outer member 22 relative to the inner member 13 will provide Aa correof the threaded y l member .22' is resiliently elongated, the

to the axisofathe outer member.. 22. For

example, the` spiral slot 27``t`e`nds `tofrnove to the yposition shown `in broken linesby the reference character 27-a when the outer memberf `221s .thus resilientlyf elnsled- The forward end of the outer-` toward the end of the inner tubular member 13,

ange'in the' inwardlydirected force "of the y 12. Preferably, 'u

The resiliency of the heat-treated steel in the outer member 22 is lsuch that the outer member is urged to assume its unstressed shape and` position shown in full lines in Figure 3. When the outer member 22 has been resiliently elongated, its longitudinal dimension is slightly longer so that in effect the end wall 25 is in the position of the broken lines shown by the reference character 25-a. Under longitudinal tension, the forward end of the outer member 22 is under such stress that the forward end then revolves slightly in the direction of the curved arrows circling the forward end of the member 22 in Figure 3 and thusmodify the form shown in full lines in Figure 3. It is thus seen that by the novel construction here disclosed and the utilizing ofthe principle of my invention, a tine adjustment in the gripping action of a pusher may be obtained. When more or less gripping force is required, the pusher may be readily adjusted by turning the outer member 22 relative to the inner member 13 and thus imparting just the required amount of radially inward force upon the pads 18 and 19.

After adjusting the position ofthe outer member 22 relative to the inner member 13 as described, the assembly of members 13 and 221is turned relative to support 16 to the point where the rear end of outer member 22 abuts the forward end of the support 16. Thus the support 16 by its jamming action frictionally resists further turning of outer member 22 relative to inner member 13.

The present disclosure includes that contained in the appended claims, as well as that of the foregoing description.

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and thatV numerous changes in the details of construction and the -thereof being chamfered to provide a camming surface .therearound disposed at an included angle of more than 45 degrees to the axis of the feed member, and a shell member concentrcally mounted around said feed member, said shell member having an internal shoulder adjacent the forward end thereof nterengaging the said camming surface of said feed member, said shell memberand said feed member at an axial distance rearwardly from said interengaged camming surface and shoulder havingcomplementary threaded portions threadablyinterlocked, said shell member along its length intermediate said shoulder and its respective said threaded portion having a plurality of spirally disposed slots provided g therein at circumferentially spaced locations therearound,

the said shell member intermediate said slots being resiliently distortable under axial tension, the adjustment of the threaded interlocking of said threaded portions relative to said shoulder engaging said camming surface varying the longitudinally directed resilient tension imposed. by the resilient shell member upon said camming surface by the said shoulder, said longitudinally directed tension of said shoulder on said camming surface urging said fingers radially inward toward said stock whereby said pad portions engage said stock in accordance with the degree of said tension. p 2. A pusher for advancing stock extending axially of the pusher comprisingin combination, concentrcally disposed members, the first of said members having resilient fingers adapted to exert radially inward directed force for gripping said stock in accordance'with said inward force, the second of said members being resiliently exf tendible in a longitudinal direction, said first member and second member adjacent their forward ends having interengaged camming surfaces adapted to move said resilient fingers radially inward upon tension of the second member urging the camming surface of the second member in a rearward direction, said first member and second member at an axial distance rearwardly of said camming surfaces being threadably interconnected by complementary threads concentric with the common axis of said members, said second member having a plurality of spirally disposed slots spaced circumferentially therearound, said second member intermediate said slots being resiliently distortable to provide resilient elongation of said second member, adjustment of the threaded interconnection of said members to vary the spacing of the threaded interconnection along said irst member from said interengaged camming surfaces varying the longitudinal resilient tension on said camming surfaces by the resiliently distortable elongation of said second member, the inward force on said fingers by said camming surfaces causing said resilient fingers to provide a radial inward force adjustably determined by the said varying of the said threaded interconnection along the first member.

3. In a pusher for advancing stock along the axis of the stock comprising the combination lof resilient linger means for gripping said stock, camming means for moving said finger means radially inward for gripping of said stock in accordance with the force imparted by the camming means on said finger means, resilient tension means for exerting force on said camming means longitudinally of said finger means to move said linger means radially inward under longitudinal resilient tension of said resilient tension means, and adjustable means for varying the degree of longitudinal resilient tension provided by said tension means.

4. In a pusher for advancing stock in increments along its axis, the combination of stock-gripping means disposed about saidr axis and adapted to be moved radially inward toward said axis for gripping said stock, camming means engaging said stock-gripping means for moving said stock-gripping means radially inward, resilient tension means disposed `concentrically of said stock-gripping means for resiliently urging said camming means in a direction longitudinally of said pusher, and adjustable connecting means interconnecting said resilient tension means and said stock-gripping means for adjustably varying the resilient tension of the tension means on sai camming means whereby the force of the camming means moving the stock-gripping means radially inward may be adjustably determined.

5. In a pusher vfor advancing stock along its axis, the combination of a first tubular member adapted to .accommodate stock therein along said axis, said first tubular member having resilient feed fingers formed at its forward end and having an annular portion adjacent its rearward end, said fingers being adapted to carry pads for gripping said stock, said pads gripping the stock with a force dependentr upon the inward thrust of said fingersv toward said axis, the Vforward end of said first tubular member being chamfered to provide an annular camming surface disposed at more than 45 degrees to said axis, and a second tubular member mounted concentrically around said first tubular member, said second tubular member having an internal annular shoulder adjacent its forward end and interengaging said camming the first tubular member to cammingly force said feed fingers inwardly toward said axis upon the urging of said shoulder against said camming surface longitudinally surface of member toward said rearward end, said second tubular member having a threaded end portion concentric with, and ihreadably engaged to, `said annular portion of the first tubular member, the said second tubular member intermediate said shoulder and the said threaded end portion having spirally disposed portions resiliently distortable to permit resilient elongation of said second tubular member under longitudinal tension, said resilient elongation vbeing adapted to urge said shoulder against said camming surface toward said rearward end, the longitudinal tension applied to said second tubular member being adjustable by varying the threaded engagement of the threaded end portion of said second tubular member along the annular portion of said first tubular member.

6. in a pusher of said first tubular for advancing stock therethrough along its axis, the combination of stock-gripping means mov-r able toward said axis for gripping said stock, longitudinally movable means concentric with and carried by said stock-gripping means, camming means operatively connecting said stock-engaging means and said longitudinally movable means for moving said stock-engaging means toward said axis upon longitudinal movement in one direction of said movable means, and resilient means operatively connecting said stock-gripping means and said movable means ble means in said one direction. y

7. In a pusher for advancing stockitherethrough along its axis, the combination of stock gripping means movable toward said axis for gripping said stock, longitudinally movable means concentric with and carried by said stockgripping means, camming means operatively connecting said stock-engaging means and said longitudinally movable means for moving said stock-engaging means toward said axis upon longitudinal movement in one direction of said movable means, resilient means urging said movable means in said one longitudinal direction, and adjustable means for adjustably varying the tension of said resilient means to obtain the required amount of inward movement of said stock-gripping means.

8. ln a pusher for advancing stock therethrough along its axis, the combination of stock-gripping means movable toward said axis for gripping said stock, longitudinally movable means concentric with and carried by said stock-gripping means, camming means operatively connecting said stock-engaging means and said longitudinally movable means for moving said stock-engaging means toward said axis upon longitudinal movement in one direction of said movable means, resilient means operatively connecting said stock-gripping means and said movable means for resiliently urging said movable means in said one direction, and adjustable means for adjustably varying the resilient urging by said resilient means to obtain the required amount of inward movement of said stock-gripping means.

9. The combination of a hollow feed member having References Cited in the iile of this patent UNITED STATES PATENTS 2,159,388 route May 23, 1939 2,426,200 ort-,en Aug. 26, 1947 2,741,483 Cox Apr. 1o, 1956 for resiliently urging said movafeed member and a hollow actu- 

